How many steps of 2FA are required to access your account as mentioned by Charles-Tim?
I can't help but to nitpick this part: those aren't "steps of 2fa" he's talking about Also wallet like bBockstream Green has 2FA wallet. It has both 2-of-2 and 2-of-3 2FA wallet.
It's Green's "MultiSig Shield" 2FA wallet feature that utilizes MultiSig which can be 2-of-2 (default) or 2-of-3 which is about the number of required signatures and cosigners.